Some documentation fixes (#3027)

axum-core/Cargo.toml

@@ -57,4 +57,3 @@ allowed = [
 
 [package.metadata.docs.rs]
 all-features = true
-rustdoc-args = ["--cfg", "docsrs"]

axum-core/src/extract/rejection.rs

@@ -42,7 +42,7 @@ define_rejection! {
     #[body = "Failed to buffer the request body"]
     /// Encountered some other error when buffering the body.
     ///
-    /// This can  _only_ happen when you're using [`tower_http::limit::RequestBodyLimitLayer`] or
+    /// This can _only_ happen when you're using [`tower_http::limit::RequestBodyLimitLayer`] or
     /// otherwise wrapping request bodies in [`http_body_util::Limited`].
     pub struct LengthLimitError(Error);
 }